Search Publications
Asymmetries of solar coronal extreme ultraviolet emission lines
Peter, H.
Context. The profiles of emission lines formed in the corona contain information on the dynamics and the heating of the hot plasma. Only recently has data with sufficiently high spectral resolution become available for investigating the details of the profiles of emission lines formed well above 106 K. These show enhanced emission in th…
Probing quiet Sun magnetism using MURaM simulations and Hinode/SP results: support for a local dynamo
Solanki, S. K.; Danilovic, S.; Schüssler, M.
Context. Owing to the limited spatial resolution and the weak polarization signal coming from the quietest regions on the Sun, the organization of the magnetic field on the smallest scales is largely unknown.
Aims: We obtain information about the magnetic flux present in the quiet Sun by comparing radiative MHD simulations with observations, …
Velocity vectors of a quiescent prominence observed by Hinode/SOT and the MSDP (Meudon)
Schmieder, B.; Chandra, R.; Berlicki, A. +1 more
Context. The dynamics of prominence fine structures present a challenge to our understanding of the formation of cool plasma prominence embedded in the hot corona.
Aims: Observations performed by the high resolution Hinode/SOT telescope allow us to compute velocities perpendicular to the line-of-sight or transverse velocities. Combining simul…
Distribution functions for magnetic fields on the quiet Sun
Stenflo, J. O.
The statistical properties of the highly structured magnetic field of the quiet Sun are best described in terms of distribution functions, in particular the probability density functions (PDF) for the flux densities and the angular distribution for the orientations of the field vector. They are needed to test the validity of various MHD simulation…
Coronal hole boundaries evolution at small scales. II. XRT view. Can small-scale outflows at CHBs be a source of the slow solar wind
Doyle, J. G.; Madjarska, M. S.; Subramanian, S.
Aims: We aim to further explore the small-scale evolution of coronal hole boundaries using X-ray high-resolution and high-cadence images. We intend to determine the fine structure and dynamics of the events causing changes of coronal hole boundaries and to explore the possibility that these events are the source of the slow solar wind.
M…
Observations of a rotating macrospicule associated with an X-ray jet
Solanki, S. K.; Inhester, B.; Curdt, W. +2 more
Aims: We attempt to understand the driving mechanism of a macrospicule and its relationship with a coronal jet.
Methods: We study the dynamics of a macrospicule and an associated coronal jet captured by multi-spacecraft observations. Doppler velocities in both the macrospicule and the coronal jet are determined by EIS and SUMER spectra. …
On the power spectrum of solar surface flows
Meunier, N.; Roudier, T.; Rieutord, M. +4 more
Context. The surface of the Sun provides us with a unique and very detailed view of turbulent stellar convection. Studying its dynamics can therefore help us make significant progress in stellar convection modelling. Many features of solar surface turbulence like the supergranulation are still poorly understood.
Aims: The aim of this work is …
Dynamics of isolated magnetic bright points derived from Hinode/SOT G-band observations
Veronig, A.; Utz, D.; Hanslmeier, A. +3 more
Context. Small-scale magnetic fields in the solar photosphere can be identified in high-resolution magnetograms or in the G-band as magnetic bright points (MBPs). Rapid motions of these fields can cause magneto-hydrodynamical waves and can also lead to nanoflares by magnetic field braiding and twisting. The MBP velocity distribution is a crucial p…
Comparing eclipse observations of the 2008 August 1 solar corona with an MHD model prediction
Riley, P.; Linker, J. A.; Mikić, Z. +7 more
Context. The structure of the white-light and emission solar coronas and their MHD modelling are the context of our work.
Aims: A comparison is made between the structure of the solar corona as observed during the 2008 August 1 total eclipse from Mongolia and that predicted by an MHD model.
Methods: The model has an improved energy formu…
Evidence of small-scale magnetic concentrations dragged by vortex motion of solar photospheric plasma
Vargas Domínguez, S.; Balmaceda, L.; Domingo, V. +2 more
Vortex-type motions have been measured by tracking bright points in high-resolution observations of the solar photosphere. These small-scale motions are thought to be determinant in the evolution of magnetic footpoints and their interaction with plasma and therefore likely to play a role in heating the upper solar atmosphere by twisting magnetic f…